Eiki LC-WB42N, Service Manual

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Troubleshooting
No Picture
No picture with all of
input sources
Check signal processing stage and LCD driving stage;
Check RGB S&H signals at test points TP5B, TP5G, TP5R.
Check power supply circuit 15.5V and peripheral circuit.
Check ICs IC501, IC51, IC561, IC401, IC01 and peripheral circuits.
Check HDMI interface stage;
Check IC7001<HDMI Driver> and peripheral circuit.
No picture with HdMI
input source only
No picture with Pc input
source only
Yes
No
No
No
Check following steps.
Check AV source selecting and decoding stage;
S-Video source
Check S-video signal (Y/C).
S-C signal is applied to pin 108 of IC01<System Control>, and S-Y
signal is applied on pin 18 of IC01.
S_SW signal (S-VIDEO:L) is input to pin 6 of IC01<System Control>.
Composite video source
Check composite video signal (Video).
The composite video signal is applied to pins 109 of IC01 <System
Control>.
Component source
Check component signal(YCbCr).
SOG1 signal is applied to pin 15 of IC01<System Control>, Y signal
is applied to pin 106 of IC01<System Control>, Cr signal is applied
to pin 214 of IC01<System Control> and Cb signal is applied to pin
215 of IC01<System Control>.
No picture with video
input sources
Yes
Check PC source stage;
Computer source
Check RGB signals on PC1.
R1 signal is applied to pin 7 of IC2201<AD Conventer>, G1 signal is
applied to pin 12 and B1 signal is applied to pin 19 of IC 2201.
HV sync signals are applied to pins and 44 of IC2201<AD
Conventer> as the HS1 and VS1 signals.
Check RGB signals on PC2 .
R2 signal is applied to pin 22 of IC2201<AD Conventer>, G2 signal is
applied to pin 24 and B2 signal is applied to pin 28 of IC 2201.
HV sync signals are applied to pins 4 and 45 of IC2201<AD
Conventer> as the HS2 and VS2 signals.
Yes
Yes